The instant invention relates to an automatic stone setting machine and more particularly to a vibratory feed escapement and a pick-up quill therefor.
Costume jewelry ornaments, such as rhinestones, are usually held in settings with prongs that are bent over the top of the stones in a manner similar to the settings of real diamonds. For many years, the setting procedures were performed manually, requiring significant manpower and labor to mass produce large quantities of costume jewelry articles. Workers manually oriented the rhinestones in the settings and then used a manual setting tool to bend the prongs over the tops of the stones. In response to increasing labor costs, automatic stone setting machines have heretofore been developed to eliminate the slow, repetitive labor. As will hereinafter be more fully explained, automatic stone setting machines of the general type known in the art are operative for automatically setting a plurality of individual stones into a continuous chain of interconnected settings. It is pointed out that for purposes of mass production, the rhinestones are commonly set into an interconnected chain of settings and thereafter, the chain is divided into individual sections which are used to make earrings, tennis bracelets, necklaces and other types of costume jewelry articles.
The heretofore known automatic stone setting machines generally comprise a rigid base, a toothed wheel rotatable upon the base for holding and advancing the chain of individual settings, a feed mechanism for holding and orienting the rhinestones in the proper position for pick-up, and a pick-up mechanism for picking up an individual stone and setting it into one of the settings on the chain. The feed mechanism comprises a vibratory parts feeder having a vibrating bowl, and a feed plate or escapement on the bowl which channels the rhinestones into position for pick-up. The pick-up mechanism comprises a pick-up quill which is spring mounted within a setting tool. The pick-up quill includes a central bore through which a vacuum is applied. The pick-up quill is mounted on a reciprocating arm which moves the pick-up quill into position to pick up a stone in the escapement and then back into position over the top of setting. For pick-up of a stone, the quill is received over the top of the stone wherein the vacuum is applied through the central bore in the pick-up quill to the flat top of the stone. The flat top of the stone blocks the vacuum flow of air through the quill and the stone is thereby retained at the end of the quill. The vacuum remains activated and the arm is moved back into position over the setting wherein the arm is then actuated downwardly onto the setting. The pick-up quill is spring loaded inside a setting tool so that when the arm is moved downwardly onto the setting, the stone is placed into the setting and the setting tool continues to move downwardly to bend the prongs over the top of the stone thereby retaining the stone within the setting. The vacuum source is then deactivated, and the chain advanced so that the next setting is moved into position. It can thus be seen that the automatic stone setting machine is operative for picking up an individual rhinestone from the escapement, placing the stone into a setting, bending the prongs of the setting over the stone, and advancing the chain to move the next setting into position.
Although the heretofore known automatic stone setting machines have generally been found to be effective, there are several design flaws which often cause the machines to pick up and set stones improperly, thereby causing defects or flaws in the continuous chain of settings. Defects in the chain of settings requires that the chain be sectioned more frequently than is necessary, thereby causing sections of chain to be wasted. One particular reason for the defective settings is the improper orientation of the stones at the pick up position. The heretofore known vibratory feed escapements have been found to regularly channel upside-down or improperly oriented rhinestones into the pick-up position. Further, the centrally located vacuum port of the quill enables the quill to pick up incorrectly oriented stones because the central hole in the quill is easily blocked by the pointed bottom of the stone or the angled side edges of the stone. Occasionally, it has been observed that a stone is oriented in a position that will not block the vacuum port and therefore the quill is prevented from picking up the stone. Still further, it has been found that even when the queued stone is properly oriented at the pick-up point, the movement of the queued stone while being picked-up can often flip the next adjacent stone into an improper position. There is thus no currently available means for determining if there is a stone present on the quill, and further, when there is a stone on the quill, if the stone is in the correct orientation.